drm/amd/display: add SW_USE_I2C_REG request.

[Description]
This is for DC_I2c arbitration use between HW use/SW use and DMCU use.

Signed-off-by: Charlene Liu <[e-mail]>
Reviewed-by: Krunoslav Kovac <[e-mail]>
Reviewed-by: Tony Cheng <[e-mail]>
Acked-by: Bhawanpreet Lakha <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.c

···
 	struct dce_i2c_hw *dce_i2c_hw)
 {
 	uint32_t i2c_setup_limit = I2C_SETUP_TIME_LIMIT_DCE;
+	/* we have checked I2c not used by DMCU, set SW use I2C REQ to 1 to indicate SW using it*/
+	REG_UPDATE(DC_I2C_ARBITRATION, DC_I2C_SW_USE_I2C_REG_REQ, 1);
 
 	if (dce_i2c_hw->setup_limit != 0)
 		i2c_setup_limit = dce_i2c_hw->setup_limit;
···
 
 	set_speed(dce_i2c_hw, dce_i2c_hw->original_speed);
 
-	/* Release I2C */
-	REG_UPDATE(DC_I2C_ARBITRATION, DC_I2C_SW_DONE_USING_I2C_REG, 1);
 
 	/* Reset HW engine */
 	{
···
 	/* HW I2c engine - clock gating feature */
 	if (!dce_i2c_hw->engine_keep_power_up_count)
 		REG_UPDATE_N(SETUP, 1, FN(SETUP, DC_I2C_DDC1_ENABLE), 0);
+	/* Release I2C after reset, so HW or DMCU could use it */
+	REG_UPDATE_2(DC_I2C_ARBITRATION, DC_I2C_SW_DONE_USING_I2C_REG, 1,
+		DC_I2C_SW_USE_I2C_REG_REQ, 0);
 
 }
 

drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.h

···
 	I2C_SF(DC_I2C_DDC1_SETUP, DC_I2C_DDC1_DATA_DRIVE_SEL, mask_sh),\
 	I2C_SF(DC_I2C_DDC1_SETUP, DC_I2C_DDC1_INTRA_TRANSACTION_DELAY, mask_sh),\
 	I2C_SF(DC_I2C_DDC1_SETUP, DC_I2C_DDC1_INTRA_BYTE_DELAY, mask_sh),\
+	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_SW_USE_I2C_REG_REQ, mask_sh),\
 	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_SW_DONE_USING_I2C_REG, mask_sh),\
 	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_NO_QUEUED_SW_GO, mask_sh),\
 	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_SW_PRIORITY, mask_sh),\
···
 	uint8_t DC_I2C_DDC1_INTRA_TRANSACTION_DELAY;
 	uint8_t DC_I2C_DDC1_INTRA_BYTE_DELAY;
 	uint8_t DC_I2C_SW_DONE_USING_I2C_REG;
+	uint8_t DC_I2C_SW_USE_I2C_REG_REQ;
 	uint8_t DC_I2C_NO_QUEUED_SW_GO;
 	uint8_t DC_I2C_SW_PRIORITY;
 	uint8_t DC_I2C_SOFT_RESET;
···
 	uint32_t DC_I2C_DDC1_INTRA_TRANSACTION_DELAY;
 	uint32_t DC_I2C_DDC1_INTRA_BYTE_DELAY;
 	uint32_t DC_I2C_SW_DONE_USING_I2C_REG;
+	uint32_t DC_I2C_SW_USE_I2C_REG_REQ;
 	uint32_t DC_I2C_NO_QUEUED_SW_GO;
 	uint32_t DC_I2C_SW_PRIORITY;
 	uint32_t DC_I2C_SOFT_RESET;